Study evaluates toxins’ effects on autism

Researchers at The University of Texas Health Science Center at Houston (UTHealth) and the University of the West Indies (UWI) have been awarded a $2.8 million grant to continue studying the role of certain genes and environmental toxins in autism spectrum disorders (ASDs) in Jamaican children.

Dr. Mohammad Hossein Rahbar, director of Clinical and Translational Sciences in the Department of Internal Medicine, is the principal investigator on this five-year grant awarded by the National Institute of Environmental Health Sciences.

“This project sets the stage for developing long-term collaborations with faculty at UWI in Kingston, Jamaica, to expand our capacity for conducting large-scale, population-based ASD studies in Jamaica,” said Rahbar, director of the Biostatistics, Epidemiology, and Research Design component of the Center for Clinical and Translational Sciences at UTHealth.

Since 2009, with funding from the National Institute of Child and Human Development and Fogarty International Center, Rahbar and his team have studied the interaction of five heavy metals found in Jamaican soil and food with genes to affect ASDs. This research will expand to investigate the role of certain genes and polychlorinated biphenyls (PCBs), organochlorine pesticides (OCs), and aluminum in ASDs. As an island nation, Jamaica has specific sources of exposure to environmental contaminants. PCBs and OC pesticides are suspected to be in the country’s seafood and agricultural products.

In March 2011, UWI received a grant from the Japanese Special Fund titled JA Kids: The Jamaican Birth Cohort Study 2011. This grant will involve 5,500 expectant mothers in Jamaica, who will be enrolled in their third trimester and whose children will be studied until age 2.

UTHealth researchers will collaborate this UWI research team by utilizing relevant data collected from this birth cohort to investigate factors associated with certain environmental toxins, particularly in utero exposures.

“We will have an opportunity to write future grants in collaboration with colleagues at the UWI to follow up on these children in order to assess their health outcomes,” Rahbar said.

Initial research focused on the following toxins: mercury, arsenic, lead, cadmium, and manganese. Rahbar and his team found that none of these metals are related to ASD in Jamaican children. However, they did discover a link between older age of biological parents and children being born with ASD.

Autism spectrum disorders are complex, neurodevelopmental and behavioral disorders characterized by impairments in social interaction and communication and repetitive, sometimes obsessive, behaviors. According to the Centers for Disease Control and Prevention, a conservative estimate is that one in every 88 children has an ASD.

Co-investigators from The University of Texas School of Public Health are Dr. Jan Bressler, assistant professor in the Human Genetics Center, and Dr. Eric Boerwinkle, professor and director of the Division of Epidemiology, Human Genetic, and Environmental Sciences. Co-investigator Dr. Katherine Loveland, is a professor of psychiatry and behavioral sciences, and UWI is represented by Dr. Maureen Samms-Vaughan.